Excessive valve train noise
 

Ever since I put my LQ4 back together (ported 853 heads, LS7 lifters, 210*/218* .551 lift on 116 LSA) I've had a ticking noise in what sounds to be the top end. The engine runs strong, but is pretty noisy. It seems to be the loudest on the passenger side of the engine. The whirring I can live with, but there also sounds like it has a slight knock to it as well. I'm pretty certain that it's coming from the valve train.

This is far from a radical combo and feel it should sound near stock. The lobes are a little aggressive, so I expected a little bit of noise, but you can barely hear the exhaust over the engine itself.
When using an adjustable push rod, my measured (via caliper) pushrod length at zero lash was 7.230. An extra .050 for lifter preload would put me at 7.280. I ordered 7.300 and threw it all together. On startup it sounded pretty nasty, but started quieting down as the lifters pumped up. I had a steady and consistent knock that was coming from the valve train.
After this I found many people say that wasn't enough preload and that the LS7 lifters like between .060 to .100. I ordered 7.350's and threw it back together. IMO, it's slightly better, but still much louder than what I had expected.

With 7.300's I had about 1 rocker bolt turn of preload past zero lash to 22 lb/ft, with the 7.350's I have right at 2 turns. Can anyone provide any insight to what this might be? Do just suck that bad when it comes to measuring for push rods? Is it possible that I've over shot the optimum preload and I'm now hearing the lifter cup bottoming out? Is there something else entirely that I may be missing? Thinking it could be rocker related, I did swap them between banks to see if the noise followed suit. It doesn't appear to.
Any insight someone can provide would be greatly appreciated. I'm getting close to calling defeat and taking it in to have another set of eyes and ears on it.

w/ 7.300 push rods http://www.youtube.com/watch?v=vI0emQAcegk
w/ 7.350 push rods http://www.youtube.com/watch?v=ziH1Y1KUUkw

is that a small base circle cam??? i used 7.4 pushrods with my tr224 camshaft. pull the valve covers, hook the coils back up, make a shield to block oil, start truck, use a hammer(handle end) to see if you can apply pressure to rockers and see if noise goes away??? there are other ways too.

I've put in a call to find out about the base circle, but don't expect to hear back for the next few days. (It's a Vinci Ultra-Torque if anyone else may know) Because of the measurements I've gotten out of the push rods, I'm assuming it's a somewhat standard circle. If it were smaller I believe I'd need even longer push rods.
One reason for the shorter than usual push rods is due to the push rod cup sitting .050 higher in the LS7 lifter compared with stock.

I'm assuming you're meaning I should lightly hold down the push rod end of the rocker with a hammer? Once the motor cools down a little and I can get the valve cover off I'll give it a shot.

I did pull the valve cover and tried pushing on the rocker. Pushing at the valve tip didn't seem to have much effect. Prolonged pushing on the lifter side (~5 seconds) seems to compress the lifter and produces excess lash.

Out of curiosity, I did break out a 7.4 pushrod and measured turns to 22 lb/ft. I came up with a little over 2 1/4 turns on the exhaust, 2 1/2 on the intake. With the 7.350's I have right at 2 turns on the exhaust, 1 3/4 on the intake.

A neighbor stopped by while I was out in the garage. He listened to it as well. Both of us feel that it's definitely in the valve train. He mentioned it sounded loose, and that he'd try the stock 7.4's to see if it cleared up. Even though it goes against all measurements that I've taken, I'm considering trying it to see if it quiets down.

may be a dumb question but hows your oil pressure?

Not a dumb question at all. It's about 45 lbs cold idle, 40 lbs hot. I did also insure that I'm getting oil to the top of each rocker. I feel confident that the lifters are pumping up properly.

I broke out the dial indicator and directly measured preload this morning. It appears I have ~.80 exhaust, and ~.100 intake. Am I too tight on the intake side causing issues? Should I run it to see if it quiets down eventually?

I picked up this motor used. Did a full set of bearings, seals, oil pump, and timing chain before throwing it in the truck. That's when I noticed a noise that I likened to a bad lifter or bent pushrod. I decided to pull it back apart to do heads, cam, lifters and pushrods. Is there any other noise that would be similar to valve train noise?

I would run the stock 7.4s..

Out of curiosity, I did put the stock 7.4's in this afternoon. Even though it does seem like an insane amount of preload, I think the engine is a very small bit quieter. Unfortunately it's still about the same. I'm about ready to pull the trigger on a new set of rockers to insure they're not making the noise. They all feel fine, but I'm just not certain they're not the source.

Before blowing another few hundred on rockers or another set of push rods I'm going to make a call to a local shop to at least have someone else take a look at it. I'd like to see what they come up with for push rod measurements. I'm also going to call Vinci again to see if I can get the base circle for this cam. I didn't even think to measure it before throwing it in.

Sounds like an exhaust leak. Did you re-use your factory exhaust hardware? LSx motors have noisy valve train especially when you add headers. I'd say you have a little to much preload on the intake but the exhaust side is about right. Make sure your using a adjustable pushrod length checker and not trying to check preload by turns on the rocker hardware. If the motor is healthy it may just be noisy...